1. Technical Field
The present invention relates to an information processing apparatus and a license distribution system which transmit license information for permitting the reproduction of a content to a reproducing device participating in a domain, and relates to an information processing apparatus and a license distribution system which can offer a privilege related to a license in accordance with the participation of a reproducing device in a domain.
2. Description of Related Art
Conventionally, a content such as music, video, or images has been circulated as the digital content with high convenience which can be stored or duplicated with suppressed degradation. Accordingly, the digital content is used via a communication network such as the Internet or digital broadcasting, and distributed to many reproducing devices to be viewed or listened to.
To promote the circulation and frequent use of the digital content, there is proposed a system in which a privilege is offered in accordance with the use of the digital content such as, e.g., consecutively viewing or listening to a series content, or viewing or listening to a content in specific hours (for example, Japanese Laid-Open Patent Publication No. 2004-145867).
However, since the digital content has the problem of the piracy resulting from its easiness to duplicate, Digital Rights Management which requires permission by license when the digital content is viewed, listened to, or duplicated is essential.
To prevent the piracy, there is proposed a system in which a plurality of personal computers (hereinafter referred to as “PCs”) or devices managed in, e.g., a home network are organized into one group, and each group is provided with a shared license so that the digital content can be viewed, listened to, or duplicated freely (for example, Japanese Laid-Open Patent Publication No. 2004-110816). Such a group is also termed a domain, and devices belonging to the domain share a domain key to implement the circulation of the content within the domain. As a result, unlimited spreading of the digital content can be prevented and the piracy by duplicating the digital content can be minimized.
Moreover, by providing a license to be given with a specific expiration date, unauthorized use of the content by using duplicated or altered license can be minimized.